A rapid prototyped atmospheric non-thermal plasma-activated aerosol device and anti-bacterial characterisation.

Non-plasma technologies are being extensively investigated for their potential to mitigate microbial growth through the production of various reactive species. Predominantly, studies utilise atmospheric non-thermal plasma to produce plasma-activated liquids. The advancement of plasma-liquid applications has led to the investigation of plasma-activated aerosols (PAAs).

Exploring hydrodynamic cavitation for citrus waste valorisation in Malta: from beverage enhancement to potato sprouting suppression and water remediation.

The endorsement of circular economy, zero-waste, and sustainable development by the EU and UN has promoted non-thermal technologies in agro-food and health industries. While northern European countries rapidly integrate these technologies, their implementation in Mediterranean food-supply chains remains uncertain. We evaluated the usefulness of hydrodynamic cavitation (HC) for valorizing orange peel waste in the fresh orange juice supply chain of the Maltese Islands.

Auxetics and FEA: Modern Materials Driven by Modern Simulation Methods.

Auxetics are materials, metamaterials or structures which expand laterally in at least one cross-sectional plane when uniaxially stretched, that is, have a negative Poisson's ratio. Over these last decades, these systems have been studied through various methods, including simulations through finite elements analysis (FEA). This simulation tool is playing an increasingly significant role in the study of materials and structures as a result of the availability of more advanced and user-friendly commercially available software and higher computational power at more reachable costs.

The Traffic Light System: A user-friendly alternative for gait data representation.

Background: Instrumented gait analysis is an established procedure in biomechanical assessment, requiring specially-trained analysts to interpret the complex graphical output generated.

Research Question: Does a new method of visual representation of lower limb kinematic gait analysis data provide a reliable and valid method of interpretation of biomechanical data for healthcare professionals?

Methods: An innovative system based on the Traffic Lights System (TLS) was developed. Simulated abnormal gait was captured using a 16-camera optoelectronic motion capture system, and the results were presented in both the Traditional Graphical System (TGS) format and the new TLS.

Undifferentiated pleomorphic sarcoma of the spleen: a case report and literature review.

Background: Undifferentiated pleomorphic sarcoma is an uncommon sarcoma and its presence in the spleen is even rarer, with only a handful of cases reported in English literature. It is typically only diagnosed following histological analysis. Its rarity also means that there is little consensus over ideal management.

FeMn and FeMnAg biodegradable alloys: An and investigation.

Iron-based biodegradable metal bone graft substitutes are in their infancy but promise to fill bone defects that arise after incidents such as trauma and revision arthroplasty surgery. Before clinical use however, a better understanding of their biodegradability, potential cytotoxicity and biocompatibility is required. In addition, these implants must ideally be able to resist infection, a complication of any implant surgery.

The role of temperature and carbon dioxide climatic stress factors on the growth kinetics of Escherichia coli.

Aims: The global level of carbon dioxide and temperature in the atmosphere is expected to increase, which may affect the survival of the stress-adapted bacteria. In this study, the effect of temperature and dissolved carbon dioxide on the growth rate of Escherichia coli-eGFP tagged strain was studied, thus assessing its response to induced environmental stress factors.

Methods And Results: A kinetic assay has been performed using a microplate reader with a spectrofluorometer to determine the specific growth rates.

Fat Necrosis Following Application of a Tourniquet During Total Knee Arthroplasty.

A 60-year-old female underwent a right total knee arthroplasty but developed postoperative pain, swelling, and decreased knee range of motion. An ultrasound scan showed findings suggestive of fat necrosis at the site of previous tourniquet application. Following regular reviews, intensive physiotherapy, and analgesia, symptoms only started to resolve 5 months following the primary surgery.

Nanoparticle Food Applications and Their Toxicity: Current Trends and Needs in Risk Assessment Strategies.

Abstract: Nanotechnology has developed into one of the most groundbreaking scientific fields in the last few decades because it exploits the enhanced reactivity of materials at the atomic scale. The current classification of nanoparticles (NPs) used in foods is outlined in relation to the production and physicochemical characteristics. This review aims to concisely present the most popular and widely used inorganic and organic NPs in food industries.

Aqueous and gaseous plasma applications for the treatment of mung bean seeds.

Sprouts are particularly prone to microbial contamination due to their high nutrient content and the warm temperatures and humid conditions needed for their production. Therefore, disinfection is a crucial step in food processing as a means of preventing the transmission of bacterial, parasitic and viral pathogens. In this study, a dielectric coplanar surface barrier discharge (DCSBD) system was used for the application of cold atmospheric plasma (CAP), plasma activated water (PAW) and their combination on mung bean seeds.

Controllable Hierarchical Mechanical Metamaterials Guided by the Hinge Design.

In this work, we use computer simulations (Molecular Dynamics) to analyse the behaviour of a specific auxetic hierarchical mechanical metamaterial composed of square-like elements. We show that, depending on the design of hinges connecting structural elements, the system can exhibit a controllable behaviour where different hierarchical levels can deform to the desired extent. We also show that the use of different hinges within the same structure can enhance the control over its deformation and mechanical properties, whose results can be applied to other mechanical metamaterials.

HPLC Analysis of Phenolic Compounds and Flavonoids with Overlapping Peaks.

The identification and quantification of phenolic compounds and flavonoids in various natural food products is typically conducted using HPLC analysis. Their analysis is particularly complex since most natural food products contain a large number of different phenolic compounds, many of which have similar chemical characteristics such as polarity, which makes complete separation of all eluents extremely difficult. In this work we present and validate a method for the quantitative determination of the concentration of two compounds with similar retention times, they show overlapping peaks in a mixed solution.

The Multidirectional Auxeticity and Negative Linear Compressibility of a 3D Mechanical Metamaterial.

In this work, through the use of a theoretical model, we analyse the potential of a specific three-dimensional mechanical metamaterial composed of arrowhead-like structural units to exhibit a negative Poisson's ratio for an arbitrary loading direction. Said analysis allows us to assess its suitability for use in applications where materials must be able to respond in a desired manner to a stimulus applied in multiple directions. As a result of our studies, we show that the analysed system is capable of exhibiting auxetic behaviour for a broad range of loading directions, with isotropic behaviour being shown in some planes.

Assessing the individual microbial inhibitory capacity of different sugars against pathogens commonly found in food systems.

Highly concentrated sugar solutions are known to be effective antimicrobial agents. However, it is unknown whether this effect is solely the result of the collective osmotic effect imparted by a mixture of sugars or whether the type of carbohydrate used also has an individual chemical effect on bacterial responses, that is, inhibition/growth. In view of this, in this work, the antimicrobial properties of four sugars, namely, glucose, fructose, sucrose and maltose against three common food pathogens; Staphylococcus aureus, Escherichia coli and Salmonella enterica, were investigated using a turbidimetric approach.

Impact resistance of composite magnetic metamaterials.

In this work, through numerical studies, we show the possibility of designing composites in a form of magneto-mechanical metamaterials which are capable of exhibiting an enhanced impact resistance in comparison to their non-magnetic counterparts. We also show that it is possible to control the impact resistance of the system solely by means of the magnitude of the magnetic moment associated with magnetic inclusions inserted into the system as well as through the way how magnetic inclusions are distributed within the structure. The latter result is particularly interesting as in this work we show that through the appropriate distribution of magnetic inclusions it is possible to minimise the force that is being transferred to an object through the protective mechanical metamaterial.

Modelling the growth of pear postharvest fungal isolates at different temperatures.

The effect of temperature on the mycelium growth kinetics of four postharvest fungal isolates (i.e., Penicillium expansum, Alternaria alternata, Botrytis cinerea and Rhizopus stolonifer) was assessed.

Assessing the efficacy of zinc oxide nanoparticles against by automated turbidimetric analysis.

Public concerns about food safety have triggered a worldwide implementation of new legislations aimed at banning many of the most popular food conventional antifungal treatments. There is therefore an urgent need to identify novel and safer solutions to prevent fungal contamination of food. The antifungal effect of zinc oxide nanoparticles (ZnO NPs) against the postharvest pathogenic fungus has been investigated in this study.

Pathophysiological mechanism of post-lobectomy air leaks.

Background: Air leak post-lobectomy continues to remain a significant clinical problem, with upper lobectomy associated with higher air leak rates. This paper investigated the pathophysiological role of pleural stress in the development of post-lobectomy air leak.

Methods: Preoperative characteristics and postoperative data from 367 consecutive video assisted thoracic surgery (VATS) lobectomy resections from one centre were collected prospectively between January 2014 and March 2017.

Turbidimetric Assessment of the Growth of Filamentous Fungi and the Antifungal Activity of Zinc Oxide Nanoparticles.

Rapid assessment of fungal growth and screening antifungal compounds, such as nanoparticles (NPs), for effectiveness is a challenging procedure because no primary standards exist as they do for yeasts and bacteria. Because fungi do not grow as single cells, but as hyphal filaments, they cannot be quantified by the usual enumeration techniques used in bacteriology. The growth of three postharvest fungal isolates ( Alternaria alternata, Rhizopus stolonifer, and Botrytis cinerea) was investigated at different inoculum concentrations and in three nutrient media (Sabouraud dextrose agar, potato dextrose agar, and yeast extract dextrose agar [YED]) with a turbidimetric assay.

A mathematical model for pressure-based organs behaving as biological pressure vessels.

We introduce a mathematical model that describes the allometry of physical characteristics of hollow organs behaving as pressure vessels based on the physics of ideal pressure vessels. The model was validated by studying parameters such as body and organ mass, systolic and diastolic pressures, internal and external dimensions, pressurization energy and organ energy output measurements of pressure-based organs in a wide range of mammals and birds. Seven rules were derived that govern amongst others, lack of size efficiency on scaling to larger organ sizes, matching organ size in the same species, equal relative efficiency in pressurization energy across species and direct size matching between organ mass and mass of contents.

Physiological rules for the heart, lungs and other pressure-based organs.

Background: The adherence of the heart to physical laws, such as Laplace's Law, may act as a measure of the organ's relative efficiency. Allometric relationships were investigated to assess the heart's efficiency concerning end-diastolic and end-systolic volumes, cardiac pressurization energy, cardiac output and mass.

Methods: Data to generate allometric relationships was obtained using a literature search, identifying heart and lung data across different mammalian and bird species.

Physiological effects and mode of action of ZnO nanoparticles against postharvest fungal contaminants.

Increasing concerns continue to be expressed about health hazards and environmental pollution resulting from the use of conventional fungicides for postharvest disease control. Nanoparticles represent an alternative solution for postharvest disease management. The objective of this work was to assess the physiological effects and the antifungal efficiency of ZnO nanoparticles (ZnO NPs) against a number of fungal contaminants.

Assessing the anti-fungal efficiency of filters coated with zinc oxide nanoparticles.

Air filters support fungal growth, leading to generation of conidia and volatile organic compounds, causing allergies, infections and food spoilage. Filters that inhibit fungi are therefore necessary. Zinc oxide (ZnO) nanoparticles have anti-fungal properties and therefore are good candidates for inhibiting growth.

On the dynamics and control of mechanical properties of hierarchical rotating rigid unit auxetics.

In this work, we investigate the deformation mechanism of auxetic hierarchical rotating square systems through a dynamics approach. We show how their deformation behaviour, hence their mechanical properties and final configuration for a given applied load, can be manipulated solely by altering the resistance to rotational motion of the hinges within the system. This provides enhanced tunability without necessarily changing the geometry of the system, a phenomenon which is not typically observed in other non-hierarchical unimode auxetic systems.

Blocked Shape Memory Effect in Negative Poisson's Ratio Polymer Metamaterials.

We describe a new class of negative Poisson's ratio (NPR) open cell PU-PE foams produced by blocking the shape memory effect in the polymer. Contrary to classical NPR open cell thermoset and thermoplastic foams that return to their auxetic phase after reheating (and therefore limit their use in technological applications), this new class of cellular solids has a permanent negative Poisson's ratio behavior, generated through multiple shape memory (mSM) treatments that lead to a fixity of the topology of the cell foam. The mSM-NPR foams have Poisson's ratio values similar to the auxetic foams prior their return to the conventional phase, but compressive stress-strain curves similar to the ones of conventional foams.